George r



G. R. LEAN.

Patented Feb. 4, 1896.

UNITED STATES PATENT OFFICE.

GEORGE E. LEAN, OF CLEVELAND, OHIO, ASSIGNOR TO THE JANDUS ELECTRIC COMPANY, OF SAME PLACE.

ELECTRlC-ARC-LIGHTING SYSTEM.

SPECIFICATION forming part of Letters Patent No. 553,920, dated February 4, 1896.

4 Application filed September 2'7. 1895. Serial No. 563,907. (No model.)

To all whom it may concern:

Be it known that I, GEORGE R. LEAN, of Cleveland, in the county of Cuyahoga and State of Ohio, have invented certain new and useful Improvements in Electric-Arc Lighting; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

My invention relates to an improvement in electric-arc lighting, and more particularly to means for operating electric-arc lamps in series in multiple-arc circuits of high voltage and constant potential.

It is the object of my present invention to provide means whereby two or more lamps,

not in themselves adapted to burn in series, can be successfully operated in multiple-arc series on high-voltage constant-potential circuits.

Vith this obj ect in view, the invention consists in the combination, with a multiplearc circuit, of two or more are lamps, each having a carbon separating and feeding magnet included in series therein, a resistancecoil included in a shunt-circuit between the terminals of each lamp, each resistance-coil being adapted to compensate for increase in voltage of the arc of the lamp between the terminals of which it is connected, and a reverse winding on the magnet of each lamp included in series with said resistance-coil.

The invention further consists in certain features of construction and arrangements of parts, as hereinafter set forth and pointed out in the claims.

The accompanying drawing illustrates an embodiment of my invention.

My improvements are intended more particularly for use with are lamps such as described in the patent to William J andus, No. 543,445, in which a long are of correspondingly-high voltage is employed, and I have illustrated my improvements in connection with such lamps.

A A represent two mains, between which two are lamps B B are shown connected in multiple-arc series. Each lamp is provided with a separating and feeding magnet C, and

the frame of each lamp is preferably made with a stem or upward extension D, which serves as a means wherebyto suspend the lamp and also to receive and hold in position a coil E of resistance, the terminals of which are connected in a shunt-circuit between the terminals of the lamp. The shunt-circuit also includes a reverse or differential winding F on the magnet C of the lamp, but this re verse or diiferential winding is so constructed as not to be sufiiciently strong to raise the armature in case of an interruption of the current in the coil of the magnet C.

When two or more are lamps, such as the J andus lamp above referred to, are placed in multiple-arc series, (without the provision of the shunt-resistance coils E and the reverse or differential windings F,) each lamp will draw its are through the agency of the magnet C, but if one lamp should draw a longer are than the other both lamps would be affected equally instead of correcting only the lamp which has drawn the excessive arc. Each coil E is so constructed that when there is any increase of the length of the are beyond the normal, and consequent rise in voltage at the terminals of any one of the series of lamps, the excess will flow through the shunt-coils E F of that particular lamp and thus weaken its magnet by robbing it of that amount of current and also weakening it by the differential effect of the coil F and cause the lamp to feed, owing to the weakened magnet C, and thus correct the length of the are without affecting the other lamps in the series.

Each shunt-circuit, including the coils E and F, is of such comparatively low resistance as to permit an amount of current to be shunted through it commensurate with the increase of voltage at the lamp -terminals caused by the lengthening of the arcs In other words, the resistance-shunt circuit of one lamp will compensate for any increase of voltage caused bythe lengthening of the arc of that lamp, rob the magnet C of such excessive current and further weaken the magnet by the differential effect of the coil F, so as to permit the carbon to feed and the length of the arc to right itself without affecting the other lamp or lamps in the circuit.

My improvements may also be used in corn nection with single lamps in multiple and also with regular series lamps.

Ilaving fully described my invention, what I claim as new, and desire to secure by Iietters Patent, is-

1. In an arc-lighting system, the combination with a n'iulti Jle-arc circuit, of two or more are lamps included in series in said multiple-arc circuit, a shunt-circuit around the terminals of each lamp, a resistance-coil in each shunt-circuit, and a reverse or ditlerential winding on the magnet of each lamp and included in said shunt-circuits in series with said resistance-coils, substantiallyas set forth.

2. I11 an are-lighting system, the combina tion with a multiple-arc circuit, of two or more are lamps, each having a carbon separating and feeding magnet, included in se ries therein, a resistance-coil included in a shunt-circuit between the terminals of each lamp each resistance-coil being adapted to compensate for increase in voltage of the are of the lamp between the terminals of which it is connected, and a reverse windin on the magnet ot' each lamp included in series with said resistance-coil, substantially as set forth.

3. In an arc-lighting system, the combination with. two or more are lamps, each hav ing a separating and feeding magnet, of a shunt-circuit between the terminals of the lamp including a resistance, and a differential winding on the magnet oi eachlamp and.

included in. said shunt-circuits, said dii't'erential winding not being sul'licient to cause the armature of the magnet to be raised in case of an interruption of the current in the coil of said magnet, substantially as set forth.

4. In an electric-lighting system, the com bination with two or more are lamps, each having a carbon separating and feeding magnet, of a resistance included in the shunt-em cuit between the terminals of each lamp,

each resistance-coil being adapted to com- 

